scholarly journals Molecular Phylogeny of Unicellular Marine Coccoid Green Algae Revealed New Insights into the Systematics of the Ulvophyceae (Chlorophyta)

2021 ◽  
Vol 9 (8) ◽  
pp. 1586
Author(s):  
Tatyana Darienko ◽  
Cecilia Rad-Menéndez ◽  
Christine N. Campbell ◽  
Thomas Pröschold

Most marine coccoid and sarcinoid green algal species have traditionally been placed within genera dominated by species from freshwater or soil habitats. For example, the genera Chlorocystis and Halochlorococcum contain exclusively marine species; however, their familial and ordinal affinities are unclear. They are characterized by a vegetative cell with lobated or reticulated chloroplast, formation of quadriflagellated zoospores and living epi- or endophytically within benthic macroalgae. They were integrated into the family Chlorochytriaceae which embraces all coccoid green algae with epi- or endophytic life phases. Later, they were excluded from the family of Chlorococcales based on studies of their life histories in culture, and transferred to their newly described order, Chlorocystidales of the Ulvophyceae. Both genera form a “Codiolum”-stage that serves as the unicellular sporophyte in their life cycles. Phylogenetic analyses of SSU and ITS rDNA sequences confirmed that these coccoid taxa belong to the Chlorocystidales, together with the sarcinoid genus Desmochloris. The biflagellated coccoid strains were members of the genus Sykidion, which represented its own order, Sykidiales, among the Ulvophyceae. Considering these results and the usage of the ITS-2/CBC approach revealed three species of Desmochloris, six of Chlorocystis, and three of Sykidion. Three new species and several new combinations were proposed.

Symbiosis ◽  
2020 ◽  
Vol 82 (3) ◽  
pp. 175-188
Author(s):  
Thomas Pröschold ◽  
Tatyana Darienko

Associations of freshwater sponges with coccoid green algae have been known for a long time. Two types of coccoid green algae, which are commonly assigned as zoochlorellae, are recognized by morphology: small coccoids (< 3 μm) without pyrenoids and larger Chlorella-like algae (4–6 μm) with pyrenoids. Despite their wide distribution in some freshwater sponges, these green algae were never studied using a combined analysis of morphology and molecular phylogeny. We investigated several endosymbiotic strains isolated from different Spongilla species, which were available in culture collections. Phylogenetic analyses of SSU and ITS rDNA sequences revealed that the strain SAG 211-40a is a member of the Chlorellaceae and represents a new species of the newly erected genus Lewiniosphaera, L symbiontica. The phylogenetic position was confirmed by morphology and ITS-2 barcode. The endosymbionts without pyrenoid were identified as Choricystis parasitica by morphology and phylogenetic analyses. The comparison with free-living strains revealed the recognition of two new Choricystis species, C. krienitzii and C. limnetica, which were confirmed by molecular signatures in V9 region of SSU rDNA and ITS-2 barcode.


2021 ◽  
Vol 12 ◽  
Author(s):  
Didi Jin ◽  
Xuetong Zhao ◽  
Tingting Ye ◽  
Jie Huang ◽  
Alan Warren ◽  
...  

The Heterotrichea Stein, 1859 are a group of ciliated protists (single-celled eukaryotes) that occur in a wide variety of aquatic habitat where they play important roles in the flow of nutrients and energy within the microbial food web. Many species are model organisms for research in cytology and regenerative biology. In the present study, the morphology and phylogeny of two heterotrich ciliates, namely, Linostomella pseudovorticella n. sp. and Peritromus kahli Villeneuve-Brachon, 1940, collected from subtropical wetlands of China, were investigated using morphological and molecular methods. L. pseudovorticella n. sp. differs from its only known congener, Linostomella vorticella Ehrenberg, 1833 Aescht in Foissner et al., 1999, by having more ciliary rows (48–67, mean about 56 vs. 26–51, mean about 42) and its small-subunit (SSU) rDNA sequence, which shows a 15-bp divergence. Although P. kahli has been reported several times in recent decades, its infraciliature has yet to be described. A redescription and improved diagnosis of this species based on a combination of previous and present data are here supplied. Phylogenetic analyses based on SSU rDNA sequences revealed that the genus Linostomella is positioned within Condylostomatidae, and Peritromidae is sister to Climacostomidae with relatively low support, and the family Spirostomidae is the root branch of the class Heterotrichea.


ISRN Ecology ◽  
2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Ladislav Hodač ◽  
Christine Hallmann ◽  
Helen Rosenkranz ◽  
Fabian Faßhauer ◽  
Thomas Friedl

Phylogenetic analyses of 18S rDNA sequences from environmental clones and culture strains revealed a widespread distribution of two subaerial green algal lineages, Jenufa and Xylochloris, recently described from rainforests in southeast Asia. A new lineage of Jenufa (Chlorophyceae), most closely related to or even conspecific with J. minuta, was formed by sequences of European origin. Two more lineages of Jenufa were formed by three additional sequences from Ecuador and Panama. The other lineage was a close relative of Xylochloris irregularis (Trebouxiophyceae), probably representing a new species of the genus and distinct from the only so far described species, X. irregularis. It comprised two distinct clades each containing almost identical sequences from Germany and Ecuador. Analyses of the new sequences for both genera allowed to presume a preference of J. minuta to subaerial growth on rock or artificial hard substrates combined with a remarkable adaptation to extended periods of darkness, whereas Xylochloris may preferably occur on tree bark or in the soil.


2014 ◽  
Vol 64 (Pt_7) ◽  
pp. 2280-2304 ◽  
Author(s):  
Tomáš Pánek ◽  
Eliška Ptáčková ◽  
Ivan Čepička

Diversity of the anaerobic Heterolobosea (Excavata: Discoba) is only poorly understood, especially in marine environments. We have isolated and cultured 16 strains of anaerobic heteroloboseid amoebae and flagellates from brackish, marine and saline anoxic habitats worldwide. Phylogenetic analyses of SSU rDNA sequences and light-microscopic observations showed that all the strains belong to the family Psalteriomonadidae, the main anaerobic lineage of Heterolobosea, and that they represent eight species from the genera Monopylocystis, Harpagon and Pseudoharpagon. Seven species are newly isolated and described here as Monopylocystis minor n. sp., Monopylocystis robusta n. sp., Monopylocystis elegans n. sp., Monopylocystis disparata n. sp., Harpagon salinus n. sp., Pseudoharpagon longus n. sp. and Pseudoharpagon tertius n. sp. Amoebae, cysts and the ultrastructure of the genus Pseudoharpagon are presented for the first time.


2021 ◽  
Vol 8 ◽  
Author(s):  
Zhishuai Qu ◽  
Hongbo Pan ◽  
Congcong Wang ◽  
Honggang Ma ◽  
Thorsten Stoeck ◽  
...  

Studies on cyrtophorian ciliates (Cyrtophoria) have accumulated much knowledge on morphological taxonomy and molecular phylogeny, and the general classification and phylogenetic relationships of most families have thereby been revealed. However, the phylogenetic position of the family Gastronautidae Deroux, 1994 remains uncertain. This is due to the presence of specialized characteristics (in particular a circumoral kinety in a closed circle), and most importantly, the lack of molecular data of this family. In addition, TrithigmostomaJankowski, 1967 holds a special position among genera in Chilodonellidae Deroux, 1976 due to its divergent characteristics. In the present work, we studied a new gastronautid, Gastronauta paraloisi sp. n., and three populations of Trithigmostoma cucullulus (Müller, 1786) Jankowski, 1967, using integrative methods. Species identifications were confirmed by morphological research. We also obtained SSU rDNA sequences, which included the first available sequence of Gastronautidae. The following SSU rDNA-inferred phylogenetic analyses showed that the establishment of the family Gastronautidae is necessary, and Gastronautidae and Trithigmostoma may represent intermediate evolutionary links in the order Chlamydodontida.


2021 ◽  
Vol 12 ◽  
Author(s):  
Mingzhen Ma ◽  
Yuqing Li ◽  
Qingxiang Yuan ◽  
Xuetong Zhao ◽  
Khaled A. S. Al-Rasheid ◽  
...  

Four suctorian ciliates, Cyclophrya magna Gönnert, 1935, Peridiscophrya florea (Kormos &amp; Kormos, 1958) Dovgal, 2002, Heliophrya rotunda (Hentschel, 1916) Matthes, 1954 and Dendrosoma radians Ehrenberg, 1838, were collected from a freshwater lake in Ningbo, China. The morphological redescription and molecular phylogenetic analyses of these ciliates were investigated. Phylogenetic analyses inferred from SSU rDNA sequences show that all three suctorian orders, Endogenida, Evaginogenida, and Exogenida, are monophyletic and that the latter two clusters as sister clades. The newly sequenced P. florea forms sister branches with C. magna, while sequences of D. radians group with those from H. rotunda within Endogenida. The family Heliophryidae, which is comprised of only two genera, Heliophrya and Cyclophrya, was previously assigned to Evaginogenida. There is now sufficient evidence, however, that the type genus Heliophrya reproduces by endogenous budding, which corresponds to the definitive feature of Endogenida. In line with this and with the support of molecular phylogenetic analyses, we therefore transfer the family Heliophryidae with the type genus Heliophrya to Endogenida. The other genus, Cyclophrya, still remains in Evaginogenida because of its evaginative budding. Therefore, combined with morphological and phylogenetic analysis, Cyclophyidae are reactivated, and it belongs to Evaginogenida.


2020 ◽  
Vol 12 (14) ◽  
pp. 16979-16992
Author(s):  
Sharada Jagannath Ghadage ◽  
Vaneeta Chandrashekhar Karande

Blue green algae are the photosynthetic prokaryotes representing a wide distribution in habitat, i.e., temperate, tropical, and polar region.  Paddy fields are the best studied aquatic ecosystems on earth which fulfill all the necessary demands required for blue green algal growth.  Blue green algal role in enhancement of paddy yield has been studied worldwide.  Sustainable utilization of an organism for community use depends on how successfully the ecology of that organism is understood.  Twenty-eight chroococcalean blue green algal taxa were recorded from the study area.  They were taxonomically investigated and found to belong to two families and 11 genera.   The first family Chroococcaceae was the largest family with 10 genera and 26 species while the second family Entophysalidaceae had only one genus and two species.  The genus Gloeocapsa from the family Chroococcaceae exhibited largest species diversity (21.42%), as well as taxa Chlorogloea fritschii of family Entophysalidaceae showed species abundance from the study area.  All heterocystous blue green algal forms are capable of fixation of atmospheric N2.  Many of the non-heterocystous or unicellular blue green algae also have the capacity of N2 fixation.  The taxonomical documentation of chroococcalean blue green algae provide information about such indigenous unicellular blue green algae which will help in the development of niche specific inoculants as biofertilizers for rice fields of the study region.  


Author(s):  
Izaz Khuram ◽  
Nadeem Ahmad ◽  
Samin Jan ◽  
Sophia Barinova

AbstractFreshwater green algal biofouling of boats refers to the accrual of freshwater green algae on boats immersed in water. The current research focused on the morphological characteristics of the isolates, species ecology, and the physicochemical properties of the water at the sampling sites. Two localities, Haji Zai and Sardaryab, were sampled at the Kabul River in the district of Charsadda, Pakistan. Freshwater green algae causing biofouling were isolated from the boats. A total of three genera: Cladophora, Rhizoclonium, and Spirogyra with fifteen species belonging to the families Cladophoraceae and Zygnemataceae were observed. Statistical analysis reveals significant stimulation of green algal species in the boats’ fouled communities by increases in water temperature, conductivity, and Total Suspended Solids (TSS). The algal growth at the Haji Zai site is suppressed by TDS in autumn (Pearson −0.56) and is stimulated by water temperature in spring (Pearson 0.44). At the Sardaryab site, algae were stimulated in spring by pH of water (Pearson 0.61), and suppressed by Total Dissolved Solids (TDS) in autumn (Pearson −0.43). Statistical analysis indicates that pH, conductivity, and temperature are the main factors determining the algal biofouling in the Kabul River.


Phytotaxa ◽  
2018 ◽  
Vol 372 (1) ◽  
pp. 51 ◽  
Author(s):  
TATYANA DARIENKO ◽  
ALENA LUKEŠOVÁ ◽  
THOMAS PRÖSCHOLD

Chlorella-like coccoid green algae are widely distributed in many types of habitats such as freshwater, terrestrial and marine. One group of terrestrial microalgae belonging to the Trebouxiophyceae forms the monophyletic lineage of the Watanabea clade. This clade exclusively comprises of ellipsoid and spherical coccoid green algae, which traditionally have been assigned as different species of Chlorella. Within this clade, seven out of ten genera are described mainly based on phylogenetic analyses of SSU and rbcL sequences. Most of the genera are represented by only one or two species that are rarely found in natural samples. In contrast, the genus Chloroidium is widely distributed across different habitats. We investigated 34 new isolates, which were originally assigned as Chloroidium or Chlorella, using an integrative approach. The phylogenetic analyses of SSU and ITS rDNA sequences revealed nine lineages, eight of which were highly supported in all of our bootstrap and Bayesian analyses. The ITS-2/CBC approach clearly demonstrated that these nine lineages represent individual species. The haplotype network analyses revealed that three out of them were widely distributed and showed no preference for any habitat.                The comprehensive study of SSU and rbcL datasets also revealed that no clear synapomorphy could be found to support the assigned genus Parachloroidium. As a result of our findings, we proposed that both species belonging to Parachloroidium be transferred to Chloroidium. In addition, we re-established two species originally described by Chodat as new members of Chloroidium (C. lichenum, C. viscosum). Two of the nine lineages (C. antarcticum, C. arboriculum) were newly described in this study.


2019 ◽  
Vol 18 (11) ◽  
pp. 1363-1382 ◽  
Author(s):  
Janusz Błaszkowski ◽  
Piotr Niezgoda ◽  
Jéssica Nunes de Paiva ◽  
Kássia Jéssica Galdino da Silva ◽  
Raquel Cordeiro Theodoro ◽  
...  

Abstract Phylogenetic analyses of 18S–ITS–28S nuc rDNA sequences indicated that the arbuscular mycorrhizal fungus originally described as Glomus tortuosum and later transferred to the genus Corymbiglomus represents a separate, previously unrecognized clade at the rank of genus in the family Diversisporaceae (order Diversisporales, phylum Glomeromycota). The analyses located the clade between clades representing the genera Desertispora and Redeckera. Consequently, a new genus, Sieverdingia, was erected, with S. tortuosa comb. nov. The unique morphological feature of S. tortuosa is the formation of glomoid-like spores with a single-layered spore wall covered with a hyphal mantle. Importantly, the erection of Sieverdingia clarified the definition of Corymbiglomus, which currently consists of three species producing glomoid-like spores with one, three- to four-layered spore wall. The features of the innermost layer, which is hyaline, laminate, flexible to semi-flexible, indicate that it is a synapomorphy of Corymbiglomus. The definitions of Corymbiglomus and its species were emended. Moreover, the distribution of S. tortuosa and the three species of Corymbiglomus was discussed based on own studies, literature data, and molecular sequences deposited in public databases. We concluded that the distribution of S. tortuosa and C. globiferum known in environmental studies based on their partial 28S nuc rDNA sequences only may be understated because the main molecular characteristics distinguishing these species reside outside the 28S region. Finally, we described a new species in the genus Diversispora originating from Mediterranean dunes of the Peloponnese peninsula, Greece. The same phylogenetic analyses mentioned above indicated that the closest relative of the new species, producing dark-coloured spores, is D. clara, whose spores are creamy white at most.


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